Hydrofoil boat



Feb. 5, 1952 D A. B. HAZARD 2,584,347

HYDROFOIL BOAT I Filed April 11, 1950 2 SHEETS-SHEET} REST w,1

. OPERATION vxL f x; He. 1 M

Feb. 5, 1952 HAZARD 2,584,347

HYDROFOIL BOAT Filed April 11, 1950 I 2 SHEETS-SHEET 2 IN VEN TOR.

Patented Feb. 5, 1952 UNITED STATES I PATENT OFFICE.

2,584,347 HYDROFOIL BOAT Allyn B. Hazard, Albuquerque, 'N. Mex.

Application April- 11, 1950, Serial No. 155245 5, Claims. (01. 114-66.5)

The present invention relates to water craft such as boats etc. and pertains more particularly to boats ofthe type in which the hull ofv the boat emerges in its entiretyfrom the water when the craft passes from the position of rest to that of speed while the elements of support remain at least partially immersed in the water.

One object then: of the present invention is to provide a water craft of new and novel design which is capable of high speeds and which may be easily, quickly and surely maneuvered.

Another object of this-invention is to provide a new and highly efiicient water craft, simple in construction and economical to manufacture.

Still another object of this invention is to provide' means for accomplishing the above objects In the accompanying drawings I have illustrated several preferred" and practical embodiments of my invention, it being understood, how'- ever, that the drawings are merely illustrative and that my inventive-concept is susceptible of other embodiments and utilizations, and that the illustrated embodiments likewise are susceptible of a wide range of variation and modification without departing from the spirit of my invention or the: scope of. the appended. claims.

In these drawings which accompany and form a part of this specification, and in which like reference numerals have. been used to designate the same or like parts throughout. the several figures? Figure 1 is a side elevation of one. formof the hydrofoil boat of my invention having an air drive: and a water rudder. Operational and. rest waterlines are indicated.

Figure 2 is a perspective view partially broken away and partially in section showing the'hydrofoil boat of my invention, the boat having an outboard. motor drive;

Figure 3 is a view in perspective .of a control wheel system adapted for use in place of the stick. control shown in Figure 2-;

Figure 4. is a perspective view of one of struts of the hydrofoil boat shown. in. Figure 2.; illustratingv one possible'arrang'ement, of, fixed and; movable hydrofoils; H

Figure 5 is a perspective view partially broken away of. the-hydrofoilboat of my invention showing a different type. of control system, than that utilized in the-boat shown in Figure. 2; I i

Figure 6 is a view in perspective of a control wheelsystem adapted for use in place of "the stick. control shown in Figure 5; and,

Figure '7 is an end view in perspective of the boat shown in Figure 1. I i

Referring now in .detail to the drawingsand first adverting' to that form of the invention shown in Figures 1 and- -'7-, the reference numeral iii has been used to designate generally a water craft of conventional. design, having an air propeller drive 12 and a rudder M for steering. The reference numeral-l6 has been used to designategenerally a strut-member having hydrofoils t8 mounted thereon. In this particular form of the invention there are two struts Hiat the front of the boat l0 and one, strut l6 near the stern of the boat. The struts it are pivotally' mounted to theboat H by pivot means 20 so that. they may be moved forward or backward by means of a control stick or wheel which controls-the movements: of the struts 1.6. by the rope or cable 24: connecting the upper end of the. strut] Hi to the control stick.22-. The lift on a hydrofoil is proportional to the square of the velocity with which it is moved through the water and to the angle of attack. or pitch. Thus, if the control stick. 2:2 is pulledbackwards it causes the upper part of the struts It. to move backward and the lower partof. the struts, carrying, the hydrofoils 18, to move forward,. about the pivot point 20, thus causing the hydrofoils [8 carried by the strut It to increase their angle of attack or pitch which increases the lift at the front end of the boat l0: and the pitch of the boat ['0 and the lift of all hydrofoils [8, causing it to rise from the surface of the water, as is explained in greater detail hereafter. C0nversely, 'if the control stick 22' is pushed forward, the upper part/of. the. struts I6 is alsov movedfforward' while the; lower part of the struts I6 carryingjthev hydrofoils I8 is moved backward about the pivot point 20., thus decreasing the angle of attack or pitch of the hydrofoilswhich in turn decreases the lift of the hydrofoils and causes the boat to move downwardly toward the surface of the water. The boat 10 may be steered in a conventional manner by means such as the rudder assemb1yl-4,.which,.if. desired may also be connected to the control. stick'22'.

Figure 2. shows a. modified form of the watercraft of my invention. The reference numeral l0. has again been used to generally designate a side.

boat, shown in Figure 2 as aconventional type. The boat l has been shown as being driven by a conventional outboard motor 26, although it is to be understood that the principles of my invention may be readily adapted for use on any type watercraft driven by any type propelling means such as inboard motors, air drives etc. without departing from the spirit of my invention or the scope of the subjoined claims. have also illustrated a control stick 22 used to control the movements of the boat l0 on the water, although a wheel control shown in Figure '3 and designated generally by the reference numeral 28 may be equally well used. The stick 22 or the control wheel 28 are of a type previously used in controlling the movements of .airplanes through the air. A strut 30 carrying a flat plate 32 which may. have a fixed hydrofoil 3| secured thereto and a movable hydrofoil 34, as shown most clearly in Figure 4 is secured to the front of the boat l0, and two struts designatedby the reference numerals 36 and 38 are pivotally secured to the rear-of the boat on opposite'sides thereof as is shown most clearly in Figure 2. The struts 36 and 38 also have flat plates 32, which may also have fixed hydrofoils 3| secured thereto and movable hydrofoils 44 and 46 respectively mounted thereon. The details of the construction of these struts 30, 36 and 33 is shown most clearly in Figures 2 and 4. While I have illustrated the strut members as carrying one fixed and one movable hydrofoil for the sake of simplicity, it is to be understood that any number of fixed and movable hydrofoils may be carried by the struts. Attached to the outboard motor 26 are rudder pedals 48 and 50 shown pivotally mounted on the floor of the boat I0. The rudder pedals may be attached to either side of the outboard motor 26 by means of the ropes or cables 52 and 54 respectively. Thus, when the operator puts pressure on the right rudder pedal, the rudder or outboard motor will be moved in such a direction as to cause the boat to turn to the right and vice versa. A hand throttle (not shown) is placed within easy reach of the operator to control the speed of the watercraft. It should be noted at this point that all control cables or ropes may have some means for tightening and adjusting the same such as turnbuckles or the like. The stick 22 is pivotally connected to a round bar member 56 which goes through and is held in place by a collar member 58 secured to the floor of the boat I0. This arrangement permits the stick 22 to be moved backward or forward and also turned from side to side as is shown most clearly in Figure 2. A rope or cable 60 runs from the front of the stick 22 to a pivotally mounted L-shaped lever arm pivoted to a support member 64 at the bow of the boat I0. The lever arm 62 may be spring biased by a spring 66, as shown in Figure 2 and a control rod 68 extends from the long arm of the arm 16 at the rear end thereof which moves from side to side as the stick 22 is moved from side to A bolt 18 extends from the lever arm 16 through a collar member 80.

In Figure 2 I where they pass over pulleys 86 and 88 respectively and then run rearwardly along the sides of the boat l0 over pulleys 90 and 92 respectively as is shown most clearly in Figure 2. The control ropes or cables 82 and 84 pass down through the strut members 36 and 30 respectively and are attached at the bottom of said strut members to pivoted levers such as that indicated by the reference numeral 94, the said levers being attached to the movable hydrofoils 44 and 46 as is shown in Figure 2. If a control wheel 28 such as that shown in Figure 3 is used, the operation is quite similar. The control wheel 28 comprises a rod portion 98 pivotally mounted to a bracket member 96 secured to the floor of the boat l0 so that it is free to move backwards and forwards. The control rope or cable 60 is attached to the front end of the rod portion 98. A wheel member which I have designated by the reference numeral is rotatably secured to the rod portion 98 and the control ropes or cables 82 and 84 are secured to a drum I02 mounted on the shaft of said wheel portion I00, so that when the wheel I00 is rotated the control ropes 02 and 84 move with it as is shown most clearly in Figure 3.

It will thus be seen that I have introduced three types of control systems in this new and novel watercraft of my invention. The rudder pedals 48 and 50 control the direction of the boat it about the yaw axis. The control stick 22 or 98 if moved forward or backwards controls the pitch of the whole boat l0, and if the control stick 22 is moved in a sidewards direction, or if the control wheel I00 is turned the roll of the boat I0 is controlled. The operation then of the craft is rather simple. If the control stick 22 or 98 is pulled backit will move the control rope or cable 60 backwards too which in turn will move the movable hydrofoil 34 forward and thus increase its angle of attack or pitch. This means as heretofore explained that there is more lift generated by the front hydrofoil which introduces a pitching moment about the pitch axis of the craft which causes the front end of the boat to rise. When the bow of the boat rises the pitch of the whole boat I0 is increased which means that the pitch of all of the hydrofoils will be increased with the increased pitch of the boat which in turn means that the lift of all of the hydrofoils will be increased and therefore the boat will climb upwards, away from the surface of the water. If the stick 22 or 98 is pushed forward there is a reverse effect, 1. e. the movement of the stick forward moves the control rope or cable 60 forward and the spring member 66 or the water forces on the hydrofoil 34 causes the angle of attack or pitch on the movable hydrofoil 34 to be decreased, there is therefore less lift in front, the bow of the boat l0 drops the pitch of the craft I0 and the pitch of all of the hydrofoils is decreased, the lift is decreased and the boat descends toward the surface of the water.

To control the craft about the roll axis, the

- stick 22 is moved sideways or the wheel member Control ropes or 7 cables 02 and 84 are attached to the collar and run laterally, one to each side of the boat I0 100 is turned in the desired direction. To illustrate, if it is desired to bank the boat ID to the right, the control stick 22 is moved to the'right, or the control wheel I00 is turned to the right, and as previously explained this will cause the angle of attack or pitch of the movable hydrofoil 46, on the right side of the boat [0, to decrease, and at the same time the pitch of the movable hydrofoil 44 on the left hand side of the boat is increased. This then produces a rolling moment about the longitudinal axis of the boat so that the right-side of the "boat'I-Il becomes lower than the left side; Opposite movement i of thecontror sticlr 2-2 or the wheel member lumwill produce opposite results.

Whemtheright-rudderpedal 48- is pushed forward the control rope or cable 52 will move for ward and turn the rudder M- or outboard-.motor 26" in suchadirectionas to cause the bow of the boat F=to turrr to theright. Pressure by theoperator on theleft rudder pedal-50 will causethe bow of the boat l-0"to='turn t'o-the left;

Figure 5- illustrates another modification of" the new and novel Watercraft of my-invention. The

reference numeral I0" has again been used to generally designate the boat; and thereference numeral- 26-anoutboard motor" carrying whydrofoil I04 on'the lower drive shafthousing thereof. A rudderbar I0'6 ispivotally connected to a supporting bracket I08 mounted on the 'flo'or of the carry fixed hydrofoil's I8 rigidly secured thereto.

The strut members I22 andl24 are pivotal'ly secured -tothe bow of theboat Ill by means of brackets I25 and I 28 respectively. 'If'desired, the strut members I'2'2"and- I24 may be-springbiased by'means of the spring I30 in or'dertdhelp =ba1 ance out some of the drag" moment introduced into'the control system. The rod Il'fi'carries-two pulley bracket mounting members I32 and I34 carrying pulleys. I316v and. 38 respectively. Through an eye'meniber I40 carried on the stick 22-: are fastened control ropes or cables I42 and I44 which pass over the pulleys I -305 and: I 38 respectively and-the other: ends: of the control ropes or cables are secured to the upper ends of the strut members I22 and 124* respectively as is shown most clearly in Figure 5. Again tightening means such as turnbuckles are used'on all control ropes and cables in order to provide a method of keeping'slack out of the control. system and providing equal resp'onsefrom allmembers when the controls 'are uscdi by the operator of the boat. If desired; a control wheel, designated generallyby5thereferencenumeral 28, uch

as that shown in Figure. 6 may be used in place of..the control stick 22. A control rod 98 =carries a wheel member I00 rotatably mounted thereon,

said wheel member I00 having a drum I02 car ried on the shaft thereof. The previously described control ropes or cables may be wound around the drum I02 so that turning the wheel I00 will cause movement of the strut members I22 and I24. The control rod 98 is rigidly secured to a bar member I46 which turns in pivot mounts I48 and I50 secured to the floor of the boat I0. The bar member I46 carries two pulleys I50 and I52 over which pass the control ropes or cables I42 and I44 respectively as is shown most clearly in Figure 6.

The control system just described-illustrates Q the principle of rotating the struts and hydrofoils together in order 'to obtain complete control: of the new and. novelwatercraft or my inventi'on. The rudder'bar I05controlsrthedirem tion of the boat I0. about the yaw axis. If it is desired to turn the nose of the. boatto the left, the" operator simply pushes on the: left side of the rudder bar I05 which movesthe control rope or cable H2 forward and turns the rudder or outboard motor so that the boat turns left; To turn the nose-of the-boat to the right the operator merely presseson the right side of the-rudder bar I06; The speed of. the boatmay be controlled by a hand throttle (not shown) placed conveniently near theoperator. The control stick." 22 or the control wheel I00: it" moved backwardsv or forwards controls the'pitch of the whole boat I0. Thus, if the control stick 22 or control wheel IEO is'mcved backward it pulls the control ropes or cables I42, and I44- backwards, which in turn moves the upper part cf the struts I22 and I 24 backwards, thus moving the lowerpart of the struts I22 and i22 which carry the hydrofoils I8, forward, thus increasing the angle of attack or "pitch of the hydrofoil's Ill and thereby'increasing the lift on the front of'the boat I0 which introduces a pitching moment about the pitch axis of the boat I0 causing the front end of the boat to rise. When the bow of the boat rises, the pitch of the whole boat is increased which means that the pitch of all of the hydrofoils willbe increased which in turn means that the lift of all of the hydrofoils will be increased and therefore the boat will climb upwards, away from: the surface ends of the struts F22 and I 24 which in turn will cause the lower endsof the strut members I22 and I24 to move backward, thus decreasing the pitch of the hydrofoils It and consequently their lift so that the bow of the boat I0 drops, andthe pitch of the craft and the pitch of all of the hydrofoils'is decreased, the lift is thus decreased and theboat descends toward thesurfaceof the water. I

To control-the craft about the roll axis, the stick 22 is moved sideways or-the Wheel member T00- is turned in the desired direction. Thus, if it is desired to bank the boat I0 to the right, the control stick 22- is moved to the right; or the control wheel Hit-is turned to the right, and as heretofore explained this will cause the angle of attack or pitch of the hydrofoils on the right side'of the boat to decrease, and at the same time the pitch of the hydrofoils' 0n the left Side of the boat will be increased. This then produces a rolling moment about the longitudinal axis of apparent that I have produced a watercraft of new and novel design. As the lift of the hydrofoils is increased the boat hull will rise upwards from the surface of the water until it is entirely clear of the water and only the hydrofoils will remain submerged so that there is very little resistance, and very high speeds will be obtained with a comparatively small expenditure of power. In general the motion of the controls by the operator will produce a rotation in the same direction and about the same axis on the boat as the same movements of the controls in an airplane would produce about the corresponding axis in an airplane. For thi reason a hydrofoil boat equipped with airplane type controls as described in this specification would make a very desirable prefiight trainer. A flying student could become orientated to the control system of an airplane at much less expense and with much greater safety than by starting to learn in an airplane. If desired, an airplane type automatic pilot system could be adapted for use with watercraft of this type.

It is to be understood that the forms of my invention herein shown and described are to be taken as preferred and practical embodiments of the same, and that various changes may be made in the shape, size and arrangement of parts without departing from the spirit of my invention or the scope of the appended claims. For example, in larger boats it may be found desirable to incorporate booster elements in the control system. However, this would probably only be necessary in extremely large boats since there is" a booster system inherently present in the design, since a small increase in lift on one of the foils at the front end of boat will tilt the whole boat thus increasing the angle of pitch and lift of all of the hydrofoils.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. The combination with a boat hull, a tubular strut attached to said hull and projecting downwardly of the bottom of said hull, said strut being open at its lower end, a bell-crank lever pivoted at its angle within the lower open end of said strut, said lever having an upright arm projecting below said strut, a hydrofoil fixed to said upright lever arm, control means within said boat, and an operative connection between said control means and the remaining arm of said lever.

2. The combination with a boat hull, a tubular strut attached to said hull andprojecting downwardly of the bottom of said hull, said strut being open at its lower end, a bell-crank lever pivoted at its angle within the lower open end of said strut, said lever having an upright arm projecting below said strut, a hydrofoil fixed to said upright lever arm, an oscillatory control arm within said boat, and an operative connection between said control arm and the remaining arm of said bell-crank lever.

3. The combination with a boat hull, a tubular strut attached to said hull and projecting downwardly of the bottom of said hull, said strut being open at its lower end, a bell-crank lever pivoted at its angle within the lower open end of said strut, said lever having an upright arm projecting below said strut, a hydrofoil fixed to said upright lever arm, an oscillatory control arm within said boat, a shaft whereto said control arm is fixed, a rock arm projecting from said shaft, a pulley mounted on the top of said strut, and a cable carried by said rock arm extending over said pulley and connected to the remaining arm of said bell-crank lever.

4. The combination with a boat hull, a tubular strut'attached to said hull and projecting downwardly of the bottom of said hull, said strut being open at its lower end, a bell-crank lever pivoted at its angle within the lower open'end of said strut, said lever having an upright arm projecting below said strut, a hydrofoil fixed to said upright lever arm, an oscillatory control arm Within said boat, a bracket fixed to said boat adjacent the top of said strut, a second bellcrank lever pivoted at its angle to said bracket and having one horizontal arm extending over the top of said strut and its other arm extending upwardly from the bracket, a cable connecting the upwardly extending bell-crank arm and said control arm, and a link connecting said bellcrank levers. I

5., The combination with a boat hull, a tubular strut attached to said hull and projecting downwardly of the bottom of said hull, said strut being open at its lower end, a bell-rank lever pivoted at its angle within the lower open end of said strut, said lever having an upright arm projecting below said trut, a hydrofoil fixed to said upright lever arm, an oscillatory control arm within said boat, a bracket fixed to said boat adjacent the top of said strut, a second bell-crank lever piv-' oted at its angle to said bracket and having one horizontal arm extending over the top of said strut and its other arm extending upwardly from the bracket, a cable connecting the upwardly extending bell-crank arm and said control arm, a link connecting said bell-crank levers, a coiled tension spring connecting said horizontal bellcrank arm and said strut.

ALLYN B. HAZARD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 909,468 Simpson 1 Jan. 12, 1909 955,343 Meacham Apr. 19, 1910 1,095,166 Richardson Apr. 28, 1914 1,186,816 Meacham June 13, 1916 1,736,896 Yamanouchi Nov. 26, 1929 1,780,998 Curioni Nov. 11, 1930 2,491,541 Woodin Dec. 20, 1949 FOREIGN PATENTS Number Country Date 472,717 France Aug. 17, 1914 

